Thermoplastic olefin copolymer

Ethylene-cyclo-olefin copolymers have been known since 1954 (DuPont USP2 721 189) but these materials only became of importance in the late 1990s with the development of copolymers of ethylene and 2-norbomene by Hoechst and Mitsui using metallocene technology developed by Hoechst. The product is marketed as Topas by Ticona. By adjustment of the monomer ratios polymers with a wide range of Tg values may be obtained including materials that are of potential interest as thermoplastic elastomers. This section considers only thermoplastic materials, cyclo-olefins of interest as elastomers are considered further in Section 11.10. 

Thermoplastic molding applications for VDC copolymers, 25 726-727 Thermoplastic olefin polymer of amorphous structure (TOPAS), 16 113 Thermoplastic polyester bottles, recycling, 20 54-56... 

Anionic Thermoplastic olefin elastomers (copolymers of butadiene, isoprene, and styrene)... 

Thermoplastic elastomers (TPEs) are either block copolymers (SBS, SEES, SEPS, TPU, COPA, COPE) or blends, such as TPO (elastomer/hard thermoplastic, also referred to as thermoplastic olefin) and TPV (fhermoplastic vul-canizafe, blend of a vulcanized elastomer and a hard fhermoplastic). These types represent the majority of fhe TPEs other types are either specialty or small-volume materials. 

Cyclic olefin copolymers (COC)s are engineering thermoplastics derived from norbornene. An addition polymer of norbornene was originally described in 1955 (1). 

In our laboratory, polymer CE microchips in combination with EC detection have been successfully used as miniaturised devices for determination of clinically important analytes. As commented in Section 34.1.2, poly(methylmethacrylate) (PMMA) is one of the most used polymers for manufacturing microchips. Recently, cyclic olefin copolymers (COCs) such as Topas (thermoplastic olefin polymer of amorphous... 

Applications of ethylene-propylene copolymers and terpolymers include automotive (the major use area), thermoplastic olefin elastomers, single-ply roofing, viscosity index improvers for lube oils, wire and cable insulation, hose, appliance parts, and polymer modification. 

Thermoplastic Olefin. These thermoplastic elastomers are primarily blends, or block or graft copolymers, of ethylene/propylene rubber with polypropylene. 

Thermoplastic polyurethanes Acetals copolymers only Thermoplastic rubbers some only Thermoplastic olefins some only Cellulosics only certain dyes... 

The most widely used material for fabrication of microfluidic systems, and hence also microfluidic cell culture chips, is PDMS, which in many systems is utilized in combination with glass. PDMS is fabrication wise well suited for prototyping, whereas it is not in the same degree amenable to mass reproduction. A new emerging trend is, however, fabrication using thermoplastic polymers, such as pol5miethylmethacrylate (PMMA), cyclic olefin copolymer (COC) and polycarbonate (PC), which can be used for... 

The first reactor-type thermoplastic polyolefin (R-TPO) was LLDPE/PP [Yamazaki and Eujimaki, 1970, 1972]. The three-component R-TPO s (PE with PP and EPR) soon followed [Strametz et al, 1975]. PE was also polymerized in the presence of active catalyst and an olefinic copolymer [Morita and Kashiwa, 1981]. Blending amorphous co-polyolefins with crystalline PO s (HDPE, LLDPE, PP), and a filler resulted in moldable blends, characterized by excellent sets of properties [Davis and Valaitis, 1993, 1994]. Blends of polycycloolefin (PCO) with a block copolymer (both polymerized in metallocene catalyzed process) and PE, were reported to show outstanding properties, viz. strength, modulus, heat resistance and toughness [Epple and Brekner, 1994]. 

As shown in Figure 20.11, the microstructures are transferred from the master to the polymer by stamping the master into the polymer, which is previously softened by heating above its glass transition temperature. This method is limited to thermoplastic polymers, and the technique has been used successfully on a variety of polymers, including polycarbonate,i polyimide, cyclic olefin copolymer, and PMMA. The main parameters to control are the surface quality, temperature uniformity, and chemical compatibility of the master. 

Polyallomer Crystalline thermoplastic block copolymers of ethylene, propylene, and other olefins. Has good impact strength, flex life, and low density. 

The first group consists of amorphous thermoplastic engineering polymers. These are cyclic olefin polymers (COP) or cyclic olefin copolymers (COC) with ethylene. They were commercialized, for example, as Zeonex (in 1991) and Zeonar (by Zeon), as Topas (Polyplastics), Apel (Mitsui), and Alton (JSR). Topas was originally part of Ticona, before it was sold to Daicel in 2005. A Topas plant with a capacity of 30,000 tpa started up in Oberhausen, Germany, in September 2000. Until that time, world capacity from 4 pilot-scale plants was around 10,000 tpa. 

Nowadays commercial mixtures of bitumens with uncured synthetic elastomers are produced, e.g. ethylene-propylene-diene terpolymers (EPDM), styrene-butadiene sequence copolymers (SBS), and ethylene-acrylic ester-acrylic acid terpolymers (AECM). Mixtures with some thermoplastics are also commercial products, e.g. polyethylene (PE), ethylene-propylene copolymers (EPM), alpha-olefinic copolymers, atactic polypropylene (aPP), and ethylene-vinyl acetate copolymers (EVA). 

FTIR step-scan photoacoustic spectroscopy was used to study the composition of thermoplastic olefin films, as a function of depth below the surface. Experiments were completed at various modulation frequencies, enabling a stratification model to be developed. The uppermost layer (0-3 im) showed large changes in talc and PP concentration, while the layer below showed a significant decrease in both the phases. In the third layer (6-9 pm), all three phases showed the maximum values. In the fourth layer (9-12 pm), the talc concentration reduced, whilst concentrations of elastomeric copolymer of ethylene and propylene (EPR) and PP were observed, decreasing with depth (44). 

Starting in the 1980 s, a number of governmental recycling policies created a demand for recycled thermoplastic olefin (TPO) for post-consumer applications. Since polystyrenes and TPOs are not miscible, polystyrene-TPO diblock copolymers are being developed to reduce the interfacial tension in PS/TPO blends. TPOs are tough materials with low stififiiess properties. If blended with polystyrene, they improve the toughness of polystyrenes. If compatibilized, the properties of PS/TPO should be similar to styrene-hydrogenated polybutadiene rubbers. 

The category of elastomers includes a wide range of products, such as natural rubber (NR), styrene-butadiene rubber (SBR), styrene-butadiene-styrene copolymer (SBS known as thermoplastic rubber), styrene-isoprene-styrene copolymer (SIS), polyurethane rubber, polyether-polyester copolymer, olefinic copolymers, ethylene-propylene rubber (EPR) and so on (see also Table 3.16). 

Let us first review the various thermoplastic elastomers used in automotive applications. These are styrenic block copolymers (SBCs), thermoplastic olefins (TPOs) (cross-linked... 

As a consequence, before 1953, the only possible blends were those of LDPE with other polymers than PO or with elastomers (e.g., chlorosulfonated polyethylene rubber, CSR chlorinated butyl mbber, CBR ethylene/propylene/diene copolymers, EPR, EPDM thermoplastic olefinic elastomer TPE, TPO). However, in addition to the original autoclave polymerization, already in 1938, a tubular reactor was introduced and its product had different properties than that from the autoclave. Also varying the reaction condition affected the degree of short- and long-chain branching in LDPE thus, blending different LDPEs offered a way for optimizing the resin to specific applications. 

A patent on reactor-blended thermoplastic olefinic elastomer, R-TPO, was disclosed. Thus, PE was polymerized in the presence of an active catalyst and an already polymerized olefinic copolymer (e.g., ethylene-co-1-butene) or the sequence was reversed. The blend had superior resistance to environment stress cracking, and the blown film showed few fish eyes... 

Thermoplastic polyolefin (TPO) is a generic name that refers to polyolefin blends usually consisting of some fraction of polypropylene (PP), polyethylene (PE) or polypropylene block copolymer (PP-b-EP or BCPP ), and a thermoplastic olefinic rubber, with or without a mineral reinforcing filler such as talc or wollastonite. Common rubbers include ethylene propylene rubber (EPR), EPDM rubber, ethylene-octene (EO) copolymer mbber, ethylene-butadiene (EB), and styrene-ethylene-butadiene-styrene (SEBS) block copolymer rubbers. Currently, there are a great variety of commercial polypropylene homopolymers, PP block copolymers, and olefinic rubbers available to make a wide range of TPO blends with densities ranging from 0.92 to 1.1. 

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